Dan flushed, how could he have forgotten Nancy! Taking the hand that his new acquaintance offered, he hurried away. He met Tom on the Port Road about half a mile from the Inn and was truly worried to find that Nancy had not returned; he explained briefly his own delay in his expedition with the strange lady to the beach.

"It is certainly odd, though perhaps not so odd as stupid, that they should have anch.o.r.ed in the Cove just to disembark one woman's boxes. It would have been much simpler to go to the Port, as every well-bred skipper does, and had the French woman's stuff carted out. At any rate, we'll go down this afternoon and have a look at her."

By the time they reached the Inn it was noon, and still there was no word of Nancy. The dinner was a silent one, as the Marquis tactfully did not disturb his companions' preoccupation, and Mrs. Frost, who was unusually nervous, did not appear.

After the meal the two young men started for the beach. At Tom's suggestion they got a little dory from the boathouse and rowed out to the clipper. The wind had shifted to the southeast, but still there was not enough of a sea to give them any trouble; and in a few minutes they were under the bows of _The Southern Cross_. Dan hailed a seaman who was leaning over the gunwale and watching them with idle curiosity. If the man replied in French, it was in a variety of that tongue that Tom's limited attainments did not understand, and, annoyed by the incomprehensible replies, he asked for "le captaine". At length,--possibly attracted by the altercation at the bows,--the authoritative-looking person who had come ash.o.r.e in the morning in response to Madame de La Fontaine's signal, now appeared at the gunwale and glanced below at the two young men in the dory. His expression betrayed no sign that he recognized Frost. Indeed he vouchsafed no syllable of reply to the questions Dan asked in English or to those that Tom ventured to phrase in Dr. Watson's French.

He was not, they thought, an attractive person; his countenance was swarthy, his eyes were black his hair was black, his heavy jaw was shadowed by an enormous black mustachio. A kerchief of brilliant red tied about his throat gave him the appearance of the matador in a Spanish bullfight rather than the officer of an English merchantman. He glanced at the dory occasionally, shook his head silently in response to the requests to go aboard, and at length when that did not serve to put an end to them, he shrugged his shoulders and disappeared. The seaman continued to lean over the gunwale and spat nonchalantly as though that were the measure of their appreciation of this unasked-for visit.

"I move we skip up the rope," said Tom, "and explain ourselves at close quarters."

"Thanks, no," replied Dan. "Either of those two amiable gentlemen looks capable and willing of pitching us overboard. The water is too cold for bathing."

"Very well," said Tom, "I will yield to your sober judgment for the moment; but I propose to see the inside of that ship sooner or later unless she weighs anchor in the hour and sails away. But we ought to be getting to town to make enquiries about Nancy. For Heavens' sake, Dan, where do you suppose she can be?"

They rowed back to the beach, stowed the dory in the boathouse, and set out in the sleigh for Monday Port. Diligent enquiry there, in likely and unlikely places, proved fruitless. It was nightfall when they returned to the Inn.

They were greeted by the Marquis in the bar. "Mademoiselle Nancy, she has not been found?"

"No," said Dan. "I take it from your question that she has not come home yet either."

"She is not come, no. Perhaps she stays at the House on the Dunes?"

"I do not know," Dan answered tartly. "I expect her every moment, but it is idle to conceal from you, Monsieur, that we are much concerned as to her absence."

The Marquis grew sympathetic,--optimistically sympathetic. Tom clutched at his re-a.s.suring words, but Dan was even more irritated by the silence that Monsieur de Boisdhyver had maintained throughout the day.

Directly after supper Dan went into his mother's parlour, leaving the others to their own devices. The Marquis settled himself near the fire and was soon absorbed in reading an old folio; Tom wandered restlessly about, now up and down the long bar, now in the corridors, now on the gallery and in the court without.

The night, after the bright day, had set in raw and cold; a damp breeze blew from the southwest, and gave promise both of wind and rain. From his position under the Red Oak, Tom could see the red and green lights of _The Southern Cross_ at her moorings in the Cove below, and across the Neck the lighted windows of the House on the Dunes. Over all else the night had cast its black damp mantle.

As he stood watching, deeply anxious for the welfare of the girl he loved, he noticed a new light appear in one of the upper windows of the House on the Dunes--not yellow as is the light of candles, but green like the light on the port side of the clipper in the Cove. Had he not seen the lights from the other windows he could have thought it was another ship on the ocean side of the Neck.

He looked for a long time at the tiny spark in the distance, wondering what whim had induced Mrs. Meath to shade her candles with so deep a green. As he strolled back toward the Inn, he glanced through the windows of the bar where the Marquis still read by the fireside. Suddenly the old gentleman, as Tom curiously watched him, laid his book down on the table and rose from his chair. He looked about the room and then advanced to the window. Tom instinctively slipped behind the trunk of the great oak. Monsieur de Boisdhyver stood for several moments peering into the darkness. Then he turned away and crossed the room to the door into the front hall. It flashed through Tom's mind that possibly the Marquis had started on another of his mysterious tours. He ran down again into the court far enough from the house to command a view of the entire facade, and watched curiously, particularly the north wing. All was dark, save for the lights below.

Suddenly he saw the flicker of a candle in one of the windows, not of the north wing, but of the south. A moment's glance, and he made sure that it was the room occupied as a sleeping apartment by Monsieur de Boisdhyver.

The Marquis was standing by the window, with his face pressed close to the pane, peering out into the night. He still held the candle in his hand. To Dan's surprise, he placed it carefully on the broad window-sill, and drew down the dark shade to within a foot of the sill, blotting out all save a narrow band of light. Then the Marquis disappeared for several moments into the interior of the room. Dan was about to turn back into the house, when again Monsieur de Boisdhyver came to the window. He did not raise the shade, but inserted between the windowpane and the candle a strip of dark green paper. It was translucent and had the effect of sending a beam of green light southward, across the meadows and the dunes, to meet--Tom suddenly realized--the rays of the green light from the House on the Dunes.

Was it a signal being exchanged, and between whom? The coincidence of green lights from the Inn and the House on the Dunes, at the same moment, was too marked to be without significance. To what end was the Marquis de Boisdhyver exchanging mysterious signals with some one in that lonely farmhouse, and what did they mean?

Tom repressed his agitation and remained for some time watching the two green lights that glowed toward one another over the dark landscape.

Suddenly the light in the House on the Dunes was extinguished; then, momentarily it shone again, but quickly went out and left the great sweep of dunes in darkness. Two minutes later the same thing took place in the window of the south chamber of the Inn. The light flashed and was gone, flashed again and shone no more.

Tom went in, by a rear entrance, to the bar. The Marquis was seated by a table, absorbed in reading. He started as Tom entered. "Still no word of Mademoiselle?" he piped.

"Still no word, monsieur," Pembroke answered laconically. He also seated himself in the candle light and took up the last issue of the _Port News_.

"Do you know what has become of Dan?" Pembroke asked presently.

"Monsieur Frost he has been closeted with madame his mother for the past half-hour. You have no further plans for seeking Mademoiselle? For myself, I grow alarmed."

"I know nothing but what you know, monsieur. Nancy has not returned.

There has been no word of her. We shall have to wait." With tremendous effort to conceal his agitation and annoyance, Tom resumed his reading.

Monsieur de Boisdhyver glanced at him for a moment with a little air of interrogation, then shrugged his shoulders slightly and turned again to his French paper.

CHAPTER IX

MRS. FROST'S RECOLLECTIONS OF A FRENCH EXILE

After the long day of fruitless search and enquiry for the vanished Nancy, supper being over and Tom having gone outside, Dan joined his mother in the blue parlour.

Mrs. Frost was weary with waiting and anxiety, but as Dan threw himself on a couch near her chair, she watched him patiently.

"There is no clue, Dan?" she ventured at last.

"No clue, mother, not the slightest. Nancy seems to have vanished as completely as if she had dissolved into air. As you know, the house has been thoroughly searched; the servants carefully questioned; and enquiries have been made at every conceivable place in Monday Port. I have been to the House on the Dunes, and to the farmhouses on every road round about. No one has seen or heard of her. She has taken French leave, but for what reason I can't imagine."

"Nancy has not been happy for some time, Dan," said Mrs. Frost.

"No, I have fancied that she was not. But why? Do you suppose she has left us deliberately? or--". He paused uncertain whether or not to give voice to his suspicions.

"Or what?" asked his mother.

"Or she has been forced away against her will."

"Against her will!" the old lady exclaimed. "Who could have forced her?

and for what reason? Do you think she may have been kidnapped?"

"Either kidnapped or decoyed away."

"But who could have designs upon Nancy? It is more reasonable to suppose that she left of her own accord. I confess that would not altogether surprise me."

"I don't know, mother, but I have my fears and suspicions. There may be some one who has a deep interest in Nancy, who for reasons of his own, which I don't yet understand, may wish to control her movements. I wish you would tell me all you know of Nancy's origin. You have never told me;--you have never told her, I fancy,--who she really is and how you came to adopt her as your own child. I have never been curious to know, in fact I have not wanted to know, for she has always been to me precisely what a sister of my own blood would be. But now, it may help me to understand certain strange things that have happened in the last few days."

For a moment Mrs. Frost was silent. "No, I have never spoken to you or to Nancy of her early history, Dan; simply because, to all intent she has been our own. I have always wished that she should feel absolutely one with us; and I think she always has, until this winter. But of late I have noticed her discontent, her growing restlessness, and I have sometimes wondered if she could be brooding over the mystery of her early years. But she has never asked me a direct question; and I have kept silent."

"I think now, mother," Dan replied, "it is your duty to tell me all you know."

"I have no reason, my dear, to keep anything from you. I should have told you years ago, if you had asked me. There is not much to tell. You may remember when you were a boy about six or seven years old, a French exile came to the Inn, a military gentleman, who had left France in consequence of the fall of the great Napoleon."

"Yes, I remember him distinctly," said Dan. "He used to tell stories to Tom and me of his adventures in the wars. Tom was speaking of him only the other day."